✨ feat(vscode): 重写注释排成一队，整个扩展一次只跑一段

OpenPencil 同一时间只能开一个画板，两段同时画会互相掐断。所有预览、所有文件的重写（第一轮和接着说）排成一队，前一段写成、出错、被叫停后按先后自动开始下一段；问 AI 照旧最多同时 3 个。
排着的那一轮记在扩展端（rewriteCurrent 的 queued），块下面写「排队中」、能取消排队，切标签页、页面重新加载后照样显示。

vscode/webview-ui/src/codeReader/qa.test.ts

@@ -130,6 +130,25 @@ describe('重写注释的状态：和问 AI 同一套', () => {
     state = chatReducer(state, { type: 'answer', askId: 'r1', question: SKILL, text: '' })
     expect(asksOf(state, IF)[0]).toMatchObject({ question: SKILL, status: 'running' })
   })
+
+  it('扩展端说排着队就显示排队中，轮到了变成在写；收起这块时排着的和在写的一样留着；取消了照停下记', () => {
+    let state = chatReducer(EMPTY_CHAT, { type: 'ask', askId: 'r1', anchor: IF, question: '', images: [] })
+    state = chatReducer(state, { type: 'answer', askId: 'r1', question: SKILL, text: '', queued: true })
+    expect(asksOf(state, IF)).toEqual([{ askId: 'r1', anchor: IF, question: SKILL, images: [], text: '', status: 'queued' }])
+    state = chatReducer(state, { type: 'close', anchor: IF })
+    expect(asksOf(state, IF).map(ask => ask.status)).toEqual(['queued'])
+    state = chatReducer(state, { type: 'answer', askId: 'r1', question: SKILL, text: '' })
+    expect(asksOf(state, IF)[0].status).toBe('running')
+    state = chatReducer(state, { type: 'answerEnd', end: { askId: 'r1', status: 'stopped' } })
+    expect(asksOf(state, IF)[0].status).toBe('stopped')
+    expect(chatReducer(state, { type: 'answer', askId: 'r1', text: '晚到的', queued: true })).toEqual(state)
+  })
+
+  it('页面重新加载后：扩展端排着队的那一轮照样显示排队中、展开它那块', () => {
+    const state = chatReducer(EMPTY_CHAT, { type: 'sync', available: true, threads: [], current: [{ askId: 'r2', anchor: IF, question: SKILL, text: '', status: 'queued' }] })
+    expect(state.open).toEqual([IF])
+    expect(asksOf(state, IF)).toEqual([{ askId: 'r2', anchor: IF, question: SKILL, text: '', status: 'queued' }])
+  })
 })
 
 describe('问的时间', () => {